jabsco marine head system question

Fishtales

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do other dc things like interior lights work? the battery switches must be on.
 

seasick

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I don't think you need to check AC circuitry especially since you admit to somewhat limited electrical knowledge.

If you have a button for discharge, see i you can get to it's wires. Using a voltmeter set to DC connect one lead to a good ground and then touch the other lead each of the two wires on the push button, one at a time.You should see 12 volts or so on one of the leads but not the other. The one that has no voltage should have it when you press the button.
If neither have juice you have to work back towards the fuse panel or breaker panel.
If you do have juice at both push button leads when the button is pressed then you need to look towards the macerator wiring (near the tank?)

I like to trace voltages with one of those inexpensive test lamps that has a point like an awl and a ground wire with an alligator clip. Ni measuring just look to see if the light lights. These work well on the fuse panel too. Connect the black wire to a good ground and test both sides of each fuse holder. They should all make the light go on.
Here is a link for an assortment of test lamps but even the cheap ones form Harbor Freight will do.
 

SeaVee

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So, I tried the above method I have power to theswitch although the switch doesn’t indicate or power up. It immediately trips the 25 amp fuse in the fuse panel when I press the pump out button, does nothing on the fill level when I press that. I don’t know a lot of stuff, but I really don’t know electronics, any suggestions on next step in the troubleshooting?
 

seasick

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Clean up those connections at the tank or better yet, disconnect them after noting what goes where, make sure they aren't touching each other or anything else and then reset the breaker/fuse and press the pump out button. I am hoping that the fuse does not blow/trip. If is doesn't you either have a short at the terminal or elsewhere or the macerator pump is shot. Next step is to apply voltage directly to the macerator leads to see if it runs. If it doesn't andyou see a decent spark when you connect the voltage, the pump is shorted or frozen (stalled).
Let's try these things and go from there.
I am not sure how the flush switch is wired si I can't say if that issue is related to the pump out problem.. One at a time.
 
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Fishtales

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I'm guessing the macerator is shot. Pump her out and plan to dive in....
 

SeaVee

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I’ve got a dumb question, can you just open to see cock and let the tank out at sea with no power? Or does the macerator pump have to work to discharge it at sea?